RMac18 Posted January 23, 2013 Report Share Posted January 23, 2013 While it's not the best way to go about it, But I assume you don't have a oscope or dd1 you can set your gain with a multimeter, even though its not the ideal way. Link to comment Share on other sites More sharing options...
Jessica Posted January 23, 2013 Report Share Posted January 23, 2013 wow, 4v pre-outs and your amp is set to .2v yeah, i think you are expecting too much from a 700 to 800 watt amp. Put your amp at 3v some kenwood amps(edit Amps should read "headunits") like to have the sub level at 0, and some like it at whatever the max is. I don't have experience with that. I know you are on a budget so try this http://www.stevemead...udio-tools-map/ see if anyone is near you that has an o-scope or a dd-1 so you can set those gains right. Otherwise you will need to play a test tone with your subs hooked up and "clamp" your amp. If you don't know what clamping is, google it, then clamp that amp around 650 to 700 watts. Kenwood used to make real nice equipment, but i have lost all love for them and the stuff they make now. Sorry, but i guess that is just the way things go. edit I mean "some kenwood "headunits" like to have..." Rest in peace, walled 87 accord build log 03' Corolla build with AA Mayhem inside. My super random youtube channel and terrible camera work. Wiring comparison by CaptainzPlanetz Wire and fuse guide by Guest SyKo13 Link to comment Share on other sites More sharing options...
Joshua Dumas Posted January 23, 2013 Author Report Share Posted January 23, 2013 like i said, i never set the gain, thats just the way the amp came. and alright ill try that Link to comment Share on other sites More sharing options...
REVOofRustler Posted January 23, 2013 Report Share Posted January 23, 2013 This may be a bit hard to understand, as I'm not too great at explaining things, but I'll try to teach you a bit on what the gain (input sensitivity) actually does. So on the back of your head unit, you have the Amplifier Pre-Outs. These are where you plug the RCA cables into. Your head unit will send the music signal through those cables, to the amp where it can be "amplified" and then sent to the subwoofers. The problem is that all head units send a different voltage signal through the Amplifier Pre-Outs. The gain on your amplifier is used to "match" that voltage with the amplifier. If you have the gain set too high, it will try to amplify the signal more than it actually can which will cause clipping. Clipping will heat up both your amp and sub and will eventually damage them. However, if you have the gain set too low it won't use all of the amps potential power. Now to get into a little more detail. The gain on the amp is used to raised the voltage coming into the amp to a specific voltage where it will then be amplified again. For instance, let's say you have a head unit that can send a 2 volt signal through the RCAs and an amplifier capable of producing 2000 watts. For the sake of this example, we'll say that the gain will be used to raise the input voltage (voltage the head unit produces) to 10 volts, where it will then be "amplified" again by a factor of 200 to produce the claimed 2000 watts. If the gain is set correctly in this situation, it will amplify the input voltage by 5 (because 10v/2v=5), to bring it up to the needed 10 volts where it will then be multiplied by 200 to produce 2000 watts. However, if the gain was set for a 1 volt input signal, it would be amplifying that signal by 10, giving it a voltage of 20. The amp would then multiply that by 200, which means that the amp would be trying to output 4000 watts. Since the amp isn't capable of producing that much power, it will start drawing much power than it should from the car's electrical system and will also start sending a distorted signal to the subwoofers. After looking up your head unit, it looks like it will produce a 4 volt signal. So ideally you would want to have your gain set at the 4, or possibly even closer to 5 if you really want to play it safe. I'm unsure though if you need to turn up the subwoofer level on that Kenwood head unit for it to actually produce those 4 volts. If someone with the same head unit could chime in, that would be great! Hope this helps! 2002 Dodge Dakota 4.7 club cab - Sold 2004 Audi S4 Avant - Fi and Crescendo - Stock Bose System - http://www.stevemeadedesigns.com/board/topic/147725-2002-dodge-dakota-end-of-the-road/?hl=%202002%20%20dakota 136.4 Sealed @ 29hz 137.0 Drivers window open @ 26hz Link to comment Share on other sites More sharing options...
Joshua Dumas Posted January 23, 2013 Author Report Share Posted January 23, 2013 well i set the gain to 3 and the sub barely even hit so i turned the bass boost up quite a bit. it sounds the same as before. but back to the main point of this thread. i only have one sub hooked up to the amp right now because its not powerful enough to power both subs. should i sell my subs and buy one single sub? or should i sell my amp and buy a amp that can power both subs? im worried about not being able to power the amp though obviously selling the one sub would be cheaper but im just not sure what to choose. what would i need to upgrade if i got a 1800 or 2000 watt amp? Link to comment Share on other sites More sharing options...
Joshua Dumas Posted January 23, 2013 Author Report Share Posted January 23, 2013 and thank you very much for the explanation, i think you did a great job. so i guess having the gain at .2 was going to kill the amp and sub. well im glad i found out now than when they blew up. Link to comment Share on other sites More sharing options...
ccmotox99 Posted January 23, 2013 Report Share Posted January 23, 2013 if your amp is shutting off when you turn it up, something is wrong. I use to have the 8105 on an L7 (back when i first started off) and it pounded. Get bigger wire, make sure your grounding it to a good spot, if it's painted remove the paint, no rust either. Make sure your power going to your battery terminal isn't corroded, it could even be something as little as something with your remote wire or even your rcas. Head unit might be butting heads with the amp. Lots of different things can cause an amp to shut off, but if its shutting off on your P2s, then something ain't right.. -playing with different setups Link to comment Share on other sites More sharing options...
ccmotox99 Posted January 23, 2013 Report Share Posted January 23, 2013 well i set the gain to 3 and the sub barely even hit so i turned the bass boost up quite a bit. it sounds the same as before. but back to the main point of this thread. i only have one sub hooked up to the amp right now because its not powerful enough to power both subs. should i sell my subs and buy one single sub? or should i sell my amp and buy a amp that can power both subs? im worried about not being able to power the amp though obviously selling the one sub would be cheaper but im just not sure what to choose. what would i need to upgrade if i got a 1800 or 2000 watt amp? Don't get rid of anything. Diagnose your problem. Get a volt meter to your amp and see what the volts rest at. Your amp has PLENTY of power for those little subs, you just don't have something hooked up right. -playing with different setups Link to comment Share on other sites More sharing options...
Joshua Dumas Posted January 23, 2013 Author Report Share Posted January 23, 2013 well the amp states that the max power it can produce is only 900 watts max at 2 ohms. both subs draw 800 watts rms at 2 ohms. i thought that was what cause it to shut off. the gauge wire is 6, should i go to 4? or even lower? the grounded spot is completely cleaned off the battery terminal is somewhat corroded.... should i replace that? i think now that i fixed the gain some that might change things. thanks for all the help guys, i really appriciate it Link to comment Share on other sites More sharing options...
lifes a BOX Posted January 23, 2013 Report Share Posted January 23, 2013 the ground is going to a whole in the trunk that i sanded down so theres no paint. its making good contact If you were to pull on your ground with a little force, would it come off? If the answer is yes, grounds no good. Link to comment Share on other sites More sharing options...
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